Surgical procedures are usually used for the treatment of cellular tissues requiring direct contact of the target tissue with a medical instrument. Surgical procedures often lead to substantial trauma by exposing both the target and the intervening tissues. Furthermore, precise placement of a treating probe is difficult because of the location of the target tissue in the body, or the proximity of the target tissue to easily damage critical body organs, nerves, or other components.
Destruction of cellular tissues in situ has been used in the treatment of many diseases and medical conditions alone or as an adjunct to surgical removal procedures. It is often less traumatic than surgical procedures and may be the only alternative, wherein other procedures are unsafe. Ablative treatment devices have an advantage of using a destructive energy that is rapidly dissipated and reduced to a non-destructive level by conduction and convection, to forces of circulating fluids and other natural processes.
Devices using microwave energy, radiofrequency energy, ultrasonic energy, cryogenic, laser energy, and tissue destructive substances have been used to destroy malignant, benign, and other types of cells and tissues from a wide variety of anatomic sites and organs. Tissues treated include isolated carcinoma masses and, more specifically, organs such as the prostate, glandular and stromal nodules characteristic of benign prostate hyperplasia. These devices typically include a catheter or cannula which is used to carry a radiofrequency electrode or microwave energy antenna through a duct to the zone of treatment and applying energy diffusively through the duct wall into the surrounding tissue in the targeted directions.
Canker sores are also known as aphthous ulcerations or recurrent aphthae, which are painful sores usually formed in the mucous membrane of the mouth. The sores first appear as small red lesions that quickly whiten and then break down to form shallow ulcers. Many people, especially small children with less immunity to ulcerations, experience the pain and discomfort of canker sores for a period from several days up to a couple of weeks. While the cause of canker sores has not been identified, several pharmaceutical approaches have been taken. However, they only coat the surface of the canker sores by a relieving agent and mask the problem for temporary relief of pain and stress.
Price, Jr. in U.S. Pat. No. 5,686,095 entitled "Method of treating canker sores" teaches a method by which a fluoroquinolone is topically applied to the ulcerous area. Similarly, Alliger in U.S. Pat. No. 5,516,799 entitled "Method of treating small mouth ulcers" teaches a method of using a simple alpha hydroxy organic acid. Marcus et al. in U.S. Pat. 5,182,104 entitled "Topical virucidal composition for treatment of mucocutaneous tissue" teaches a method of topically applying composition with a virucidal impact on mucocutaneous tissue, inactivation of herpes virus and human papilloma virus as manifested in cold sores, canker sores, warts, fever blisters lesions, and aptheous ulcerations. Leeds in U.S. Pat. No. 4,466,956 entitled "Method of therapy for oral herpes simplex" discloses serial application of povidone-iodine and then application of anti-inflammatory agent. Hodosh in U.S. Pat. No. 4,191,750 entitled "Method for treating canker sores" discloses a method of applying a nitrate of potassium, lithium, sodium, magnesium, calcium or strontium. However, all the above-mentioned topical treatments are not effective because the therapeutic agent is easily swept away in the mouth of a patient. None of above-mentioned patents discloses the method for treating canker sores by heating the therapeutic fluid and forcing the heated fluid to contact the canker sores for a prolonged period treatment.
Of particular interest to the present invention are RF therapeutic protocols which have been proven to be highly effective as used by electrophysiologists for the treatment of tachycardia; by neurosurgeons for the treatment of Parkinson's disease; and by neurosurgeons and anesthetists for other RF procedures such as Gasserian ganglionectomy for trigeminal neuralgia and percutaneous cervical cordotomy for intractable pains. Radiofrequency treatment, which exposes a patient to minimal side effects and risks, is generally performed after locating the sore sites for treatment. Radiofrequency energy, when coupled with a temperature control mechanism, can supply precise energy to the device-to-tissue contact site to obtain the desired temperature for creating a lesion. It can also be used to heat the therapeutic fluid for therapeutically treating the canker sores for the optimal effect.
Imran in U.S. Pat. No. 5,281,218 entitled "Catheter having needle electrode for radiofrequency ablation" teaches a method using a needle electrode that is attached onto a catheter for radiofrequency ablation. Though a needle-like electrode is beneficial to ablate a tissue point for deep lesion, it is not disclosed that the needle electrode could possibly hold the heated therapeutic fluid for prolonged contact with the target tissue.
Edwards et al. in U.S. Pat. No. 5,456,662 entitled "Method for reducing snoring by RF ablation of the uvula" teaches a medical ablation method for reducing snoring wherein a flexible RF electrode wire is inserted into the uvula and RF energy is applied to the uvula tissue to cause internal lesions. Edwards et al. does not disclose a catheter to ablate an area, having capability for simultaneously delivering radiofrequency energy and a therapeutic agent.
While a radiofrequency procedure using an existing electrode device has had promising results, the device is exposed to the target tissue without prolonged therapeutic treatment by the therapeutic agent, resulting in inefficient treatment of canker sores. Therefore, there is a need for an improved device system and methods using the controllable radiofrequency energy for generating the needed heat to treat the canker sores and also to heat the therapeutic fluid. During RF energy delivery, the therapeutic agent, such as an anti-inflammatory agent or virucidal drug, is delivered to the lesion sites. By having a device with temperature control means and substance delivery capability, the canker sores can be treated therapeutically.